1. Field of Invention
The present invention relates to infant beds and suspension systems. In particular, it relates to a dual post strap suspense system for fixed angled or adjustable tilt beds particularly applicable to the treatment of gastroesophageal reflux disease (GERD) in infants. GERD is a common disease of infancy, which afflicts as many as 18% of otherwise healthy infants.1 GERD is predominantly caused by relaxation of the lower oesophageal sphincter.2 In other words, a doughnut shaped muscle located in the esophagus above the stomach, which constricts in healthy infants to keep stomach contents in place, fails or relaxes allowing stomach acids to travel back up the esophagus causing pain and tissue damage to the infant.
1 A. E. Carroll. M. M. Garrison, and D. A. Christakis. A Systematic Review of Nonpharmacological and Nonsurgical Therapies for Gastroesophageal Reflux in Infants. Archives of Pediatrics & Adolescent Medicine. Feb. 1, 2002; 156(2): 109-113. 2 T I Omari, C P Barnett, M A Benninga, R Lontis, L Goodchild, R R Haslam, J Dent, and G P Davidson. Mechanisms of gastro-oesophageal reflux in preterm and term infants with reflux disease. GUT An Internation Journal of Gastroenterology and Hepatology, Oct. 1, 2002; 51(4): 575-479. 3S. R. Orenstein. M. D. and P. F. Whittington, M. D. Positioning for prevention of infant gastro esophageal reflux Journal of PEDIATRICS 1983 October; 103(4): 534-7. 4S. R. Orenstein. M. C. “Prone Positioning in infant gastroesophageal reflux: Is elevation of the head worth the trouble?” Journal of PEDIATRICS 1990; 117(Pt. 1); 185-187 5 A. K. Ewer, M. E. James, and J. M. Tobin. Prone and left later positioning reduce gastro esophageal reflux in preterm infants. Archives of Disease in childhood Fetal Neonatal Edition 1999; 81:F201-F205 (November). 
Clinical studies have concluded that infants suffering from GERD benefit from being positioned with their head elevated at approximately 30 degrees in a prone position.3 Infants placed in an angled prone position cry less and sleep for longer periods of time.4 Clinical studies have also concluded that symptoms of GERD are reduced when infants are placed to sleep on their left side.5 
1 A. E. Carroll. M. M. Garrison, and D. A. Christakis. A Systematic Review of Nonpharmacological and Nonsurgical Therapies for Gastroesophageal Reflux in Infants. Archives of Pediatrics & Adolescent Medicine. Feb. 1, 2002; 156(2): 109-113. 2 T I Omari, C P Barnett, M A Benninga, R Lontis, L Goodchild, R R Haslam, J Dent, and G P Davidson. Mechanisms of gastro-oesophageal reflux in preterm and term infants with reflux disease. GUT An Internation Journal of Gastroenterology and Hepatology, Oct. 1, 2002; 51(4): 575-479. 3S. R. Orenstein. M. D. and P. F. Whittington, M. D. Positioning for prevention of infant gastro esophageal reflux Journal of PEDIATRICS 1983 October; 103(4): 534-7. 4S. R. Orenstein. M. C. “Prone Positioning in infant gastroesophageal reflux: Is elevation of the head worth the trouble?” Journal of PEDIATRICS 1990; 117(Pt. 1); 185-187 5 A. K. Ewer, M. E. James, and J. M. Tobin. Prone and left later positioning reduce gastro esophageal reflux in preterm infants. Archives of Disease in childhood Fetal Neonatal Edition 1999; 81:F201-F205 (November). 
Notwithstanding these findings, the efficacy of recommending that infants be placed in an elevated position for sleeping has come under scrutiny by the medical community due in part to the cumbersome nature of the present devices designed to maintain infants in a prone position at a 30 degree angle, see footnote 4. None-the-less, inclined infant sleeping positions for infants with GERD are commonly recommended, see footnote 1. The present invention overcomes the cumbersome aspects of the prior inventions; thereby facilitating the inclined sleeping of infants with GERD.
2. Description of Related Art
Various tilted beds and suspension systems for infants are known. Some suspense systems specifically address infant GERD, such as the Tucker Sling™ produced by Tucker Designs Ltd, http://www.tuckerdesings.com, which fits around the upper part of an angled mattress like a contour sheet and has a diaper-shaped part attached that goes between a baby's legs and fastens around the waist with hook and loop strips such that the infant is secured to the angled mattress in a diaper like harness restricting its movements during sleep. The device makes it difficult to change the infant. It also provides no sidewalls or end walls to secure the infant in a safe environment, and is similar to devices considered too cumbersome by the medical community, see footnote 4.
Guimond, U.S. Pat. No. 4,471,767 discloses a therapeutic device to secure a child to an angled support surface via securing briefs and tethers. The infant is secured therein by two ropes. The ropes pose a significant risk of strangulation and cutting off the blood supply to limbs hands fingers etcetera, if the infant tips and becomes entangled as the child moves. The ropes could also prevent a child from reaching its arms down his/her side as infants naturally do during sleep, resulting in a less comfortable sleeping position.
If the diaper harness 25 is placed over a diaper, it will be very put and tend to tilt the child's lower torso up placing the spine in an unnatural position. It could cause a downward force on the child's abdomen and possibly neck and face. The wedge mattress is not adjustable and apparently is made out of a soft foam surface, which could add to the risk of smothering relative to the safety of a bassinet mattress. No catch mechanism is provided to protect the infant if the child slips out of the harness. Nor are there sidewalls for security or to protect child if the harness fails.
Colón, U.S. Pat. No. 5,127,422 discloses an anti-reflux saddle board with a differing strap system and mount. To use the saddle board, the child's legs are spread apart in an unnatural position, which could cause blood loss to the pubic area, deformity in the skeleton/muscle structure of the thighs waist and legs, and would be uncomfortable sleeping. When the straps are secured, the child's movement would be excessively restricted at the waist and near the shoulders. Few parents of a child with GERD could rest easy with their child tightly affixed to a mattress. Parents may fear that the child will not be able to move enough to cough up fluid or something obstructing its breathing path. The infant may also slump to the left or right in this device resulting in an unnatural, uncomfortable position that could be dangerous if the infant's air way became obstructed or the child spit up in his/her sleep. The straps may also prevent the child from reaching his/her arms down by its side as infants naturally might do during sleep, again resulting in a less comfortable sleeping position. The thin loose straps (only connected by hook and loop strips) could also become entangled and if the child fell from the center crotch support mechanism the child could strangle on the straps or fall onto an unsafe surface.
This device only reclines at two angels 30 and 45 degrees. Some infants with minor symptoms, or as they start overcoming GERD, may need less severe angles of repose. The device thus presents an infant with a “cold turkey” scenario, where the child goes from upright sleeping to flat sleeping, which may cause adjustment problems.
Another drawback is that the child sleeps on a hard flat washable plastic mattress, which may not be comfortable, preventing the child from sleeping. The hard plastic mattress may not breath possibly causing the child to suffer bedsores and possible infections.
Doran et al, U.S. Pat. No. 5,014,376 discloses a wedge shaped support mattress with a support blanket to secure the infant thereto. There is nothing to keep a child from sliding off the foam wedge. This foam type wedge may provide too soft a surface for safe infant sleep, as a child can smother itself by placing its face, face down on foam.
Bowman, U.S. Pat. No. 5,439,008 discloses an infant reflux restraint apparatus employing side straps, and a head positioning support attached to a wedge shaped mattress. The inner-tube like ring/pillow is designed for positioning an infant to sleep on its back, which is not the recommended GERD treatment position, see footnotes 3 and 5. The child's movements are also severely restricted by the securing straps. The lateral support pillows, 51, 52 located on either side of the sleeping infant, excessively restrain the child, could cause chafing and may prevent the infant from assuming a left side sleep position or lowering its arms. If the straps push up into the infant's armpits thus forcing the child's arms above its head, they could—over time—cause skeletal muscle problems.
Smith, U.S. Pat. No. 4,566,449 discloses an elevated infant positioner using cut-out templates to surround and secure an infant at an inclined angle. This device claims to overcome the excessive restraint shortcomings of other art but goes too far. The child is not actively held by anything but sidewalls and gravity so that a child could slump down and fall out of this device. This device is also made of foam, which may pose a smothering hazard. It also does not allow for widely adjustable mattress reclining angles. The child's movement side to side and its ability to put its arms up or down is restricted and the device may not encourage left side sleeping. This device would have a tendency to encase the child in insulation causing a significant increase in their risk of overheating, which may be a risk factor for Sudden Infant Death Syndrome (SIDS).
Klingemann et al, U.S. Pat. No. 5,800,368 discloses another elevated infant positioner using cut-out templates to surround and secure an infant at the inclined angle, and also includes a strap securing system. This device is similar to Smith, U.S. Pat. No. 4,566,449 and is subject to all of its shortcomings. It has the added risk of infant strangulation if an infant fell with its neck over the strap system.
Cited for general interest are: Enste et al, U.S. Pat. No. 4,441,221, which discloses a child support wedge and strap system for children having multiple injuries and/or severe handicaps.
Rose et al, U.S. Pat. No. 6,292,964 discloses a wedge pillow and cushions employing no restraining or suspension equipment making it virtually useless for infants. It is primarily employed for use by adults to provide lower back and neck support.
King, U.S. Pat. No. 6,023,802 discloses an infant sleeper with sidewalls to secure an infant to a horizontal mattress support surface. The mattress reclining angle is possibly insufficient to assist in GERD therapy and is not adjustable. The straps would not hold a child therein, and the device has no safety catch mechanism. The mattress is made of foam and therefore exposes the infant to the risk of smothering and overheating.
Moscot, U.S. Pat. No. 5,700,059 discloses a vertical baby support for simulating the ordinary front and back holding positions of a baby. It does not appear to address GERD and the angle at which it holds a child appears to be too steep for prolonged sleeping and may exacerbate GERD, see footnote 4. Its suspension mechanism is restrictive and may pose the threat of strangulation.
Oswalt et al., U.S. Pat. No. 4,977,630 discloses an angled patient mover with restraints. It is geared toward use with young children rather than infants and apparently addresses mobilizing sick and injured children for transport purpose to, from, and within hospitals.
McArthur et al, U.S. Pat. No. 4,819,282 discloses a tilting mechanism for use with an infant bassinet. This device only tilts a bassinet mattress and does not secure an infant on that mattress. This device has complicated exposed metal parts that a child could be injured on if the child falls off the mattress and crawls under the inclined plane.
Yamate, U.S. Pat. No. 3,423,773 discloses an orthopedic device with a hinged bed and saddle with straps to secure thereto a patient with immobilized legs. It is probably too restrictive at waist and upper torso for GERD treatment, see footnote 4, and requires an unnatural spread leg position. To hold a child and prevent movement side to side, the waist belt would have to be secured very tightly, or the child could still slump by bending at the waist. A soft surface pillow could also be dangerous for stomach sleeping. It has no sidewalls or catch mechanism for safety if the strap suspension system fails. It also employs thin belts, which could pose a significant risk of strangulation.
Tandrup, U.S. Pat. No. 5,826,287 discloses an infant support and positioning system incorporating three releasably attachable cushions associated with a strapping system. It does not claim to address GERD, but addresses muscle tone issues and the need to secure children in car seats that are too large for them. No angled mattress support is incorporated. It also uses foam filled cylinders, which may pose an infant smothering hazard.
E. M. Du Bois et al, U.S. Pat. No. 2,697,480 discloses an angled shampoo chair to keep soapy water out of the eyes of children.
The present invention described below provides an improved infant reflux adjustable strap suspense and GERD treatment infant mattress system.